After consultation with Dr. Park, I concluded that it would be better not to depend on the Black Rock station for observations in the future--at least in the immediate future--and other points were discussed. Eventually it was determined to establish a new station near Farmington, on the eastern shore of the lake. The point selected is in an inlet so sheltered that a heavy swell in the lake will not interfere with accurate observation. At the present stage of water the spot is well adapted to the purpose, and it can be used with the water 2 feet lower or 5 feet higher. I was not able to attend personally to the erection of the pillar, but left the matter in the hands of Mr. Jacob Miller, of Farmington, who writes me that it was placed in position and the record begun on the 24th of November, 1877. The pillar is of wood, and is graduated to inches for 9 feet of its length. On the day of its establishment the reading of the water surface was 2 feet 1 inch. On the 21st of January, 1878, the reading was 2 feet 1¹⁄₂ inches. The Farmington and Black Rock pillars are 23 miles apart. The relative height of their zeros will be ascertained as soon as practicable by making coincident readings, during still weather, of the water surface at the two stations. It is already known that the Farmington zero is _approximately_ 16 inches lower than the Black Rock. A stone “bench” or monument for permanent reference has also been placed on rising ground near the observation pillar, and the two will be connected by spirit level. The Farmington bench is of gneiss, and is marked with a + in the same manner as the Black Rock. The stone was contributed by Mr. Abbott, of Farmington, and was gratuitously shaped and placed by Mr. Miller. Mr. Miller has also voluntarily assumed charge of the record, and will make or superintend the observations. It will not be practicable to visit the pillar daily, nor even at _regular_ intervals, but it is expected that the record will be as full as the one tabulated above. The following items are to be noted: 1. Time of observation, including year, month, day, and hour. 2. Reading of water surface in feet and inches. 3. Direction and force of wind. 4. Account of wind for the preceding 24 hours. 5. Name of observer. These observations will not only determine the annual gain or loss of the lake, but will in a few years give data to construct the curve of the annual tide. The history of past changes not having been the subject of record, it became necessary to compile it from such collateral data as were attainable. The enquiries inaugurated by Professor Henry have been prosecuted, and have resulted in a tolerably definite determination of the principal changes since 1847, together with the indication of a superior limit to earlier oscillations.